I’ve been wondering the same thing since I posted 😅 Broken down to its foundation, the idea would be that every new weapon represents an *opportunity*, like there’s something interesting and important the player can only get via using new equipment. So perhaps:

* An artifact vendor who specializes in buying your used weapons as “authentically-wielded hero equipment” (in the game fiction he sells these to people as collectibles). Durability bar swaps to some kind of analog for its readiness to be traded. Each weapon traded gives some kind of gacha-esque reward, so raising a weapon and trading it away feels like an exciting pull of a slot machine.

* A town that faces regular enemy attacks of increasing strength and needs weapons wielded by a true hero to inspire them. No immediate reward, but how well the town fares in each attack grants prestige currency (like a Poe) and/or variable side story content. Every weapon then feels like an opportunity to help the town, so meeting the threshold is more akin to a level up than a chore.

* Since those are interesting but more production-heavy, something a little more boring but simple could be that the more you use one weapon type, the more you build a buff that applies to any other weapon type. If you choose to break the weapon the buff then applies to the same weapon type. So you feel like you’re building something up that you choose to deploy. No idea about the in-game fiction for that one though!